The present invention relates to photocopying method and apparatus and more particularly to a photocopying method and apparatus using a so called photo sensitive sheet, in particular, photo-pressure sensitive sheet. Conventionally, in the photocopying apparatus which uses the photo-pressure sensitive sheet, an image is photocopied once on a transparent intermediate film in the same manner as photoprinting and then photocopied by using this intermediate film on a photo-pressure sensitive sheet (U.S. application Ser. No. 32,865, Mar. 31, 1987). Using this type of conventional photocopying apparatus, it is therefore time-consuming to produce an intermediate film prior to photocopying. At the same time, a large scale photocopying apparatus is required.
Moreover, the total running cost is high and the total time required is lengthy. To solve these problems, a system in which an original can be directly exposed must necessarily be developed. Many means are considered to obtain this concept. One of these is to utilize a reflected light beam after it is directly focused on the original. Upon reflection, this beam is projected on the photopressure sensitive sheet to focus images (U.S. application Ser. No. 943,195, Dec. 18, 1986).
However, this kind of imaging system requires additional optical means to radiate these reflected beams onto the photo-pressure sensitive sheet, thus resulting in a large scale system as well as great expense in total imaging time and cost. Considering these factors, the most effective imaging method is to expose the photo-pressure sensitive sheet to a light without using the intermediate film and the reflected beams.
In order to solve the problem, a photocopying apparatus is disclosed in which the original is directly attached to the monochromic photo-pressure sensitive sheet without using intermediate film (U.S. application Ser. No. 24,432, Mar. 11, 1987). This equipment uses two overlapping sheets, one of which is an original and the other a photopressure sensitive sheet (U.S. Pat. No. 4,399,209, U.S. Pat. No. 4,440,846).
Now, in a photocopying apparatus which is described in the U.S. application Ser. No. 24,432, the photo-pressure sensitive sheet is subject to damage due largely to a rugged surface of the original when the original and the photo-pressure sensitive sheet are overlapped. Usually, the original and photo-pressure sensitive sheet are overlapped. Then, frictional forces also occur between original and sheet, thus causing frictional damage.
Due to the friction caused by overlapping, a photopressure sensitive substance on the surface is often ruptured and therefore a fine photocopy finish is no feasible on a photo-pressure sensitive sheet or a transfer sheet.
Then, in said photocopying apparatus, a good photocopying quality is not attained, especially when it comes to photocopying a specific original or the like. One bottleneck problem is that the images on either sides of the original are simultaneously copied, including any figures described thereon.
This photocopying of the reverse side of the original should be avoided in this case. As long as this apparatus is concerned, images pass through optical systems interposed between the light sources and original. Only the same images as drawn on the original are projected and duplicated on the photo sensitive sheet. If images other than those on the original are to be photocopied, still further improvement is necessary.
Especially when images are to be supplemented with figures, characters, symbols ,etc. to explain more clearly or modify the image, the black/non-black imaging(exposing an original to a light through display on the liquid crystal panel) and image trimmings are conducted.